text: import subprocess
  import unittest
  from io import StringIO
  from unittest import mock
  
  from django.db import DatabaseError, connection
  from django.db.backends.base.creation import BaseDatabaseCreation
  from django.db.backends.mysql.creation import DatabaseCreation
  from django.test import SimpleTestCase
  
  
  @unittest.skipUnless(connection.vendor == 'mysql', 'MySQL tests')
  class DatabaseCreationTests(SimpleTestCase):
  
      def _execute_raise_database_exists(self, cursor, parameters, keepdb=False):
          raise DatabaseError(1007, "Can't create database '%s'; database exists" % parameters['dbname'])
  
      def _execute_raise_access_denied(self, cursor, parameters, keepdb=False):
          raise DatabaseError(1044, "Access denied for user")
  
      def patch_test_db_creation(self, execute_create_test_db):
          return mock.patch.object(BaseDatabaseCreation, '_execute_create_test_db', execute_create_test_db)
  
      @mock.patch('sys.stdout', new_callable=StringIO)
      @mock.patch('sys.stderr', new_callable=StringIO)
      def test_create_test_db_database_exists(self, *mocked_objects):
          # Simulate test database creation raising "database exists"
          creation = DatabaseCreation(connection)
          with self.patch_test_db_creation(self._execute_raise_database_exists):
              with mock.patch('builtins.input', return_value='no'):
                  with self.assertRaises(SystemExit):
                      # SystemExit is raised if the user answers "no" to the
                      # prompt asking if it's okay to delete the test database.
                      creation._create_test_db(verbosity=0, autoclobber=False, keepdb=False)
              # "Database exists" shouldn't appear when keepdb is on
              creation._create_test_db(verbosity=0, autoclobber=False, keepdb=True)
  
      @mock.patch('sys.stdout', new_callable=StringIO)
      @mock.patch('sys.stderr', new_callable=StringIO)
      def test_create_test_db_unexpected_error(self, *mocked_objects):
          # Simulate test database creation raising unexpected error
          creation = DatabaseCreation(connection)
          with self.patch_test_db_creation(self._execute_raise_access_denied):
              with self.assertRaises(SystemExit):
                  creation._create_test_db(verbosity=0, autoclobber=False, keepdb=False)
  
      def test_clone_test_db_database_exists(self):
          creation = DatabaseCreation(connection)
          with self.patch_test_db_creation(self._execute_raise_database_exists):
              with mock.patch.object(DatabaseCreation, '_clone_db') as _clone_db:
                  creation._clone_test_db('suffix', verbosity=0, keepdb=True)
                  _clone_db.assert_not_called()
  
      def test_clone_test_db_options_ordering(self):
          creation = DatabaseCreation(connection)
          try:
              saved_settings = connection.settings_dict
              connection.settings_dict = {
                  'NAME': 'source_db',
                  'USER': '',
                  'PASSWORD': '',
                  'PORT': '',
                  'HOST': '',
                  'ENGINE': 'django.db.backends.mysql',
                  'OPTIONS': {
                      'read_default_file': 'my.cnf',
                  },
              }
              with mock.patch.object(subprocess, 'Popen') as mocked_popen:
                  creation._clone_db('source_db', 'target_db')
                  mocked_popen.assert_has_calls([
                      mock.call(
                          [
                              'mysqldump',
                              '--defaults-file=my.cnf',
                              '--routines',
                              '--events',
                              'source_db',
                          ],
                          stdout=subprocess.PIPE,
                      ),
                  ])
          finally:
              connection.settings_dict = saved_settings
  